Frost shield



April 24, 1934.

J. R. THORPV FROST SHIELD Original Filed Dec. 15, 1930 Reissued Apr. 24,1934 P 9 UNITED STA Tss PATENT OFFICE \Re 45 I FROS T smnLn Joel B.Thorp, West Allis, Wis; assignor to The Fulton Company, WestAllis, Via,a corporation of Wisconsin Original No. 1,914,183, dated June 13, 1933,Serial No. 502,387, December 15, 1930. Application for reissue October20, 1933, Serial No. 694,489

QC'Iaims.

-10 to provide an improved device for maintaining clear vision through awindow, which is simple in construction-and which is moreover highlyefllcient in operation.

Many appliances intended for the, purpose of maintaining clearvision'through the windshield of an automobile or the like, haveheretofore been proposed, but all of these prior devices are more orless objectionable. In some of these prior devices, it has .-beenproposed to utilize rubber vacuum cups for the purpose of removablyattaching the appliances to the windows, relying upon the impositiveaction of the cups to hold the device in place. In others of these priorappliances, it was contemplated to utilize a heating medium, such as anelectric wire receiving current from the automobile battery or ignitionsystem, to dispel the moisture and other view obtructingcoatings whichtended to accumulate on the windshield or windows, and in these proposeddevices it was contemplated to utilize relatively complicated andineffective means for maintaining the heating wires taut and forconducting thecurrent thereto. In addition to the objects specificallymentioned, the prior devices of this'general type were alsoobjectionable because of their .inability to effectively accomplishtheir intended purpose.

It is a more specific object of the present invention'to provide variousimprovements in the constructiofi of appliances of this kind, whichwhile embodying some of the desirable features of theprior types abovereferred to, do not introduce the objectionable features thereof.

Another specific object of the invention is to provide a device formaintaining clear vision through a window, which maybe conveniently andfirmly attached to the window, or removed therefrom, whenever desired,and which does not rely upon the suction action of a set of cups tomaintain the device in place.

A further objectof the'invention is to provide an electrically heatedclear vision appliance'which is simple and compact in construction andwherein the. wires used for heating purposes are maintained taut bysimple and effective mentalities. Still another specific object of theinvention is to provide an improved frame structure for supporting asheet of transparent material in posi 0 tion adjacent to a window or thelike. Another specific object'of the invention is to provide an improvedclear vision accessory for automobile Windshields or the like, whichwill effectively prevent accumulation of objectionable matter upon theoutside or exposed surfacesof the shield, without the aid of a wiper,such as is instrufrequently applied to Windshields or the like.

A further object of the invention is to provide an improved device formaintaining clear vision through a. window, which is light and sturdy inconstruction, and which moreover presents an extremely neat appearance,permitting its use with any automobile.

Still another object of the invention is to provide an improvedaccessory for maintaining clear} vision through'a windshield or thelike, which may be manufactured at minimum cost,

W and which eliminates danger of breaking the a shield or window towhich it is applied. so

These and other objects and advantages will be apparent from thefollowing description.

I A clear conception of an embodiment-0f the invention and of the modeof. constructing and of utilizing devices built in accordance therewith,may be had by referring to the drawing accompanying and forming a partof this specification, in which like reference characters designate thesame or similar parts in the several views.

Fig. 1 is a rear view of a fragment of a frost coated vehiclewindshield, showing one of the improved frost shields applied thereto;

Fig. 2 is a view looking into one of the improved frost shields, withone of the attaching elements removed and with some of the remainingstructures also broken away:

Fig. 3 is a section through the shield, the section being taken alongthe line 3-3 of Fig. 2 looking in the direction of the arrows;

Fig. ,4- is an enlarged fragmentary section through the shield, thesection being taken along the line 4-4 of Fig. 2; and

Fig. 5 is a similarly enlarged fragmentary section taken along the line5--5of Fig. 2.

While the improved appliance will hereinafter be referred to as a frostshield, it will be understood that this device is not merely capable ofmaintaining the surface of a window to which it is applied, free fromfrost, but the device will in fact function to. maintain the window free1109i turing process.

The improved frost shield shown in the draw.- ing byway of illustration,comprises in general a one-piece continuous frame 6; a transparent sheet7 fitted within the frame 6; a sealing strip 8 secured to the frame 6 atthe periphery of the shield 7; supporting elements 9 detachablyassociated with the four corners of the frame 6; and means for creatingheat within the enclosure formed by the frame 6 and the transparentsheet 7w The frame 6 is preferably stamped from a single sheet ofrelativelythin metal, and has a continuous integral flange 19 extendinginwardly and inclined slightly toward the transparent sheet 7, as shownin Figs. 4 and 5, so that only the free edge of the flange 10resiliently engages the sheet 7 to provide a perfect seal withoutundesirably stressing the transparent sheet. The corners of the frame 6are provided with integral outwardly extending cars 11 forming pocketscontiguous with the sheet receiving portion of the frame 6, and-thesecars 11 moreover facilitate attachment of the frame 6 to the supportingelements 9.

The transparent sheet 7 is preferably formed of glass cut to properlyfit within the frame 6 and cooperable with the continuous flange 10, as

previously indicated. When the ears 11 are disposed slightly away fromthe extreme corners of the frame 6, as shown in Figs. 1 and 2, thecomers 12 of the glass sheet 7 may be cut away along straight lines, 'asindicated at the upper right hand comer of Fig. 2, and the pocketsprovided by the .ears' 11 permit the corners of the sheet 7 to overlapthe rounded corners of the frame structure without necessitatingcorresponding rounding of the comers of the glass sheet. Such roundingof the comers, of the sheet 7 is objectionable since it introducesexcessive breakage of glass during the manufac- The sealing strip 8 maybe formed of felt, rubber or other suitable material, and is attached tothe interior of the peripheral flange of the frame 6 by means of twosegregated conductor bands 13, 14 and rivets 15. The bands 13, 14

are insulated from each other by spaces at their.

adjacent ends, and also by means of insulating washers 16 coacting withthe rivets 15, so that no electrical connection exists between the bands13, 14 except through the heating means, which will be subsequentlydescribed herein. The bands 13, 14 are formed of flat stockand coactonly with the sealing strip 8 throughout substantially the entire lengthof the latter, these bands thereby constituting sections forming asubstantially continuous retainer band which is spaced from the glasssheet 7 so as to permit the sealing strip 8 to absorb the clampingpressure without sub- :lecting the sheet to excessive local stressessuch aswould result from direct contact of the band with the glass. Oneof the longitudinal edges of the sealing strip 8 snugly engages theinner surface of the glass sheet 7, while the opposite edge thereofprojects laterally beyond the periphery of the frame 6, as clearly shownin Figs. 4 and 5. When the projecting edge of the sealing strip 8 isbrought into contact with a windshield 17 or other window, and isslightly compressed, a sealed space is produced between the glass sheet7 and the inner surface of the windshield 17.

Each of the supporting elements 9 comprises from practically all kindsof vision obstructing coatings or deposits.

a block of material such as rubber, having a threaded stud 18 formedintegral therewith. The blocks of material may be dished to provide for.slight suction action during application of the elements 9 totheswindshield 17, but this suction action is not relied upon topermanently hold the elements in place- The elements 9 are cementeddirectly to the surface of the windshield 17 in order to insurepermanent union of the coacting parts, and as previously indicated, thesuction action produced by the dishing of the elements is only utilizedto hold the elements in place until the cement has become effective.

When the four supporting elements 9 have been properly positioned andpermanently attached to the windshield 17, the integral studs 18 thereofare disposed parallel to each other,

and the frame 6 may then be applied to the elements 9 by passing theelement studs through the openings 19 of the cars 11. Clamping caps 20are applicable to the studs 18 to clamp the frame 6 against the elements9 and to simultaneously compress the sealing strip 8 in order to producethe sealed space between the transparent sheet 7 and windshield 17,previously referred to. With such means of attachment, the elements 9may obviously be permanently attached to the windshield 17, while stillpermitting ready removal of the frame 6 and associated parts by merelyremoving the caps 20 and slipping the frame off of the studs 18. I

The means for heating the confined space between the glass sheet 7 andthe windshield 17, comprises a plurality of parallel properly spacedwires 21, 22, 23 and leaf springs 24, for maintaining these wirestaut-at all times. The wires '21, 22, 23 span the frame 6longitudinally, and

have their corresponding ends attached directly to the conductor band14. The opposite corresponding ends of the wires 21, 22 are attached tothe ends of the double leaf spring 24, and the corresponding end of thewire 23 is likewise attached to the free end of the leaf spring 25, themedial portion of the spring 24 and the opposite end of the spring 25being rigidly attached to the conductor band 13 by means of screws 26,27 respectively, as shown in Figs. 4 and- 5. The screws 26, 27 besidesserving to clamp the adiacentportion of the band 13 against .the sealingstrip 8, also coact with an elongated in Fig. 4, to form an electricalconnection between this terminal and the conductor band13 which iselectrically connected to the'adja'c'ent ends of the wires 21, 22, 23,and another screw 31 likewise connects the conductor band 14 with theterminal 30, thereby completing the circuit from the terminal 29 to theterminal 30 through the band 13, springs 24, 25, wires 21, 22, 23, and

band 14. The,peripheral flange of the frame 6? is notched so as to avoiddirect contact between the metal frame 6 and the conducting screws 26,27, 31, and a removable contact plug 32 and wiring 33 connected to asuitable source of electrical energy, serve to energize the heatingsystem. =1 When the supporting elements 9 have been properly positionedand permanently cemented to the inner surface of the windshield 17, theframefi should be flrst loosely applied to the studs 18 and the plug 32should then be applied to the terminals 29, 30 to cause the wires 21,22, 23 to heat and dry the air within the space ber v 19,145 tween thesheet '7 and shield 17 and to permit any moisture therein to escapebefore the sealing strip is compressed into contact with the windshield.After this initial drying operation has been effected,'the clamping capsmay be 10 heat the confined air and the heat will be radiated from theconfined body of dry air, through the glass sheet 7 and through theadjacent portion of the glass windshield 17 thereby preventingaccumulation of coatings'of moisture on the outer surfaces of the heatedglass. The lateral spacing of the wires 21, 22, 23 should be such thateifec tive distribution of the heat to all portions of the glasssurfaces, is assured, and the leaf springs 24, 25 serve to maintainthewires 21, 22, 23 taut at all times, thereby preventing the hot wireswhich are obviously elongated when heated, from sagging and from comingin contact with the adjacent surfaces of the sheet 7 and windshield 17.

' 'I'hewires 21, 22, 23 may obviously be quickly deenergized by merelywithdrawing the plug 32 from the terminals 29, 30, andthe frame 6 may,be readily removed during seasons when the .device is unnecessary, bymerely releasing the caps 20. In cases where the vision obstructingtendency is not extreme, as when the windshield is merely subjected tofog or other slight moisture deposits, the wires 21, 22, 23 may beomitted and the confined body of air will be sufficient to maintainclear vision on the adjacent external surfaces of the air confiningglass. The heating system when used, may obviously be energized from anysuitable source such as the ignition system or, battery of theautomobile, and the current is delivered through the wires 21, 22, 23\in parallel.

The sheet metal frame 6 is preferably stamped out of a single sheet ofmaterial and may be plated or enameled to present a neat appearance. Theportion, of the sheet which is cut from the center, is utilized in themanufacture of other accessories, thus eliminating waste of stock, andthe one piece frame construction insures the requisite rigidity in theassembled structure. The elements 9 may be formed of rubber or othermaterial which permits firm cementing. thereof to the windshield 17, andthe appliance has dam.- onst-rated its ability to effectively preventaccumulation of vision obstructing coatings in all kinds of weather andwithout the aid of a wiper .or other auxiliary apparatus.v The frame 6and bands 13, 14 being formed of relatively thin and resilient material,and the latter contacting only with the soft sealing strip 8, avoidsundesirably stressing the sheet 7 or the windshield '17, and theresilient flange 10 additionally protects the sheet 7 against breakageand maintains a tight joint. 1 g

It should be understood that it is not desired to limit the invention tothe exact details of construction herein shown and described, forvarious modifications within the scope of the claims may occur topersons skilled in the art.

It is claimed and desired to secure by Letters Patent: v

1. In combination, a frame, a transparent sheet coacting with saidframe, a continuous sealing strip coacting with said sheet adjacent tosaid frame, heating means within said frame adjacent to said sheet, anda'conductor band for energizing said means, said band being insulatedfrom said frame and coacting with said strip throughout substantiallyits entire length to secure the same to said frame'and in contact withsaid sheet.

2. In combination, a frame having a resilient flange, a transparentsheet having one side thereof coacting with said flange, a continuouspliable sealingstrip coacting with said frame and with the opposite sideof said sheet, heating means within said frame, and a conductor band forenergizing said means, said band being insulated from said frameandcoacting with said strip throughout substantiallyits entire length tosecure the same to said frame and in contact with said sheet. e I 3; Incombination, a frame having a peripheral wall, a transparent sheetdisposed within said wa1l,.a continuous sealing strip coacting with saidwall and with said sheet, a pair of relatively insulated conductor bandsinsulated from said frame and coacting with said strip throughoutsubstantially its entire length, and a plurality of wires connectingsaid ban 4. In combination, a frame having a peripheral wall, atransparent sheet disposed within said wall, a. continuous sealing stripcoacting with' said wall and with said sheet, a pair of conductor bandsinsulated from each other and from said frame, said conductor bandscoacting with said strip to clamp the same to said frame wall,a-plurality of heating wires spanning said frame and. connected to oneof said bands, and an independent leaf spring connecting each of saidwires to the other of said bands.

5. In combination, a frame having a peripheral wall, a transparent sheetdisposed within said wall, a continuous sealing strip coacting with saidwall and with said sheet, a pair of conductor bands insulated from eachother and from said frame, said conductor bands coacting with said stripto clampthe same to said frame wall, a plurality of heating wiresspanning said frame and connected to one of said bands, and anindependent leaf spring secured to the free end of each wire andextending at an oblique angle toward the other of said bands.

6. In combination, a frame having a clamping portion, a transparentsheet coacting with said clamping portion, acontinuous relatively softsealing strip coacting with the edge portion of said sheet in oppositionto said clamping portion, a retainer band spaced from said sheet andcoacting only with said strip throughout substantially the entire lengthof the latter to secure said strip to said frame and in contact withsaid sheet, and heating means carried by said band and frame within thelatter and adiacent, to said sheet.

7. In combination, a frame having a clamping portion, a transparentsheet coacting with said clamping portion, a continuous relatively softsealing strip coacting with the edge portion of said sheet in oppositionto said clamping portion, a retainer band comprising a plurality ofsections spaced fromeach other and from' said sheet and providing-asubstantially continuous piece coacting only with said strip throughoutsubstantially the entire length of "the latter to secure said strip tosaid frame and in contact with said sheet, and heating means carried bysaid band and frame within the latter and adjacent to said sheet. V

8. In combination, a frame having an outer wall and an inwardlyprojecting flange, a transparent sheet disposed within said wall andcoacting with said flange, a continuous relatively soft sealing stripcoacting with said sheet in opposition to said flange, a retainer bandspacedirom said sheet and coacting only with said strip throughoutsubstantially'the entire length of the latter .to secure said strip tosaid wall and in contact with said sheet, and a plurality of heatingelements secured -to said band and frame and disposed within the latteradjacent to said sheet.

9. In combination, a frame having an outer wall and an inwardly.projecting flange, a transparent sheet disposed within said wall andcoacting with said flange, a continuous relatively soft sealing stripcoacting with said sheet in opposition to said flange, a retainer bandcomprising a plurality of sections spaced from each other and from saidsheet and providing a" substantially continuous piece coacting only withsaid, strip throughout substantially the entire length of the latter tosecure said strip to said wall and in contact with said sheet, and aplurality of heating elements secured to said band and frame anddisposed within the latter adjacent-to said sheet.

JOEL R. THORP.

